syslinux: cosmetic space

"prompt" and subsequent first "label" were not separated
in any way while second "label" and forth were; let's make
the resulting isolinux.cfg a tiny bit more pretty.
regular.mk: added license note to server

It's the only installer in this collection
and it did lack any branding indeed.
regular.mk: added livecd-install-apt-cache

Carrying over metadata and packages downloaded by apt while
being run off a LiveCD is implemented as suggested in #29192.
1.1.10-alt1

- regular tweaks
gear-store-tags